The prior art is documented with examples of sanitary door knob covers or appliques. These include each of the sanitary and disposable cover of Willis, U.S. Pat. No. 6,546,594, the sanitary door knob of Millar, U.S. Pat. No. 3,314,746, the multi-surface anti-bacterial protective device of Williams U.S. Pat. No. 6,821,325, the door handle cover of Herron, Jr., US 2006/0006678, the sanitary door handle with material advancing mechanism of Hawkins, U.S. Pat. No. 4,658,469, the touchless door pull apparatus of Krawczyk, U.S. Pat. No. 6,353,971, and the sanitary door knob of Millar, U.S. Pat. No. 3,314,746.
An additional class of prior art references deals with other types of secondary systems for providing a spray or cleaning application over an existing door handle surface and this includes each of the door sanitation system of Lidahl, U.S. Pat. No. 6,508,383, the door knob sanitizing device of Butterfield, U.S. Pat. No. 6,298,521, the door handle sanitizer system and apparatus of Sasson, US 2006/0153733, the apparatus and method for providing a continuously sanitized contact surface of Dawson, U.S. Pat. No. 6,645,435, the door handle disinfecting cover dispensing system of Gaudreau, U.S. Pat. No. 6,789,695 and the device for disinfecting door handles in Callueng, U.S. Pat. No. 6,874,697.
Other references of note include the door knob insulator of Newman, US H2137 which provides an elastic cover which stretches to apply over a conventional doorknob. Mannix, Des. 427,046 teaches a door knob cover in the form of a fabric kerchief shape which is folded over the door handle and secured in place by a band.
Visco, U.S. Pat. No. 4,856,140 teaches a corrugated cover shaped body with annular arrayed, taper shaped and aperture/slit defining gripping locations which brings the user's hand in contact with the door surface when employed. Other references of note include the gripping device of Latimer, III, U.S. Pat. No. 5,664,520, the door knob stop of Chapman, Des. 329,590, the flexible door knob cover of Des. 192,150 and the molded article of Anson U.S. Pat. No. 2,731,056.